Swapping AGM Batteries for Lithium Lifepo4

[Brooksie]

I wouldn't do it if they were giving away Lion batteries. I'd just add another couple std batteries to your bank. Soon you will be having a surcharge on your insurance and having trouble at some storage yards and marinas as well. There is a lot of garbage out there on the market especially drop-ins and a lot of misinformation as well. Even purpose-built installations go bad witness the EV vehicle fires and the Boeing aircraft fires and the recent car carrier ship fires to name a few. These were all deigned systems, not drop-ins.

 

[Iggy]

What "issues"?

There are no issues of changing to LFP unless you decide to go down the "science project" installation method.

Compared to acid, and especially AGMs, LFP have no "issues". Far as I am concerned AGMs have no home anymore on a boat for a house bank of batteries. You get SLA or FLA for your start batteries and LFP for your house.

Yep!

 

[Iggy]

Some insurance companies won't cover boats with owner installed lithium banks. They will ask for the name of the ABYC certified electician that did the work. If you don't tell them about the batteries, then they may not cover you if you make a future claim.

So I would locate a nearby electrician who has done a bunch of these and have him make a proposal. It will cost a bit more than DIY but avoids lots of potential problems.

I called mine Insurance Co. In a nut shell they said. "No problem." Keep in mind that Li is becoming more and more a common thing.

 

[tiltrider1]

Lot a people confusing Lithium-ion with LiFePo4. LiFePo4 is very stable and it is extremely difficult to induce a run-a-way situation while charging( some say impossible). This is not the case for other Lithium-ion chemistries.

 

[twistedtree]

I called mine Insurance Co. In a nut shell they said. "No problem." Keep in mind that Li is becoming more and more a common thing.

Markel is the only company I have heard of with LFP-fear.

 

[Ken Kindrick]

Swapping Lithium batteries

My advice is to always, ALWAYS, hire a qualified marine electrician whenever you make changes to a marine electrical system which involves batteries, chargers, alternators. This excludes the guy on the dock who has done his own before, or the guy who is a residential electrician.

 

[Don L]

My advice is to always, ALWAYS, hire a qualified marine electrician whenever you make changes to a marine electrical system which involves batteries, chargers, alternators. This excludes the guy on the dock who has done his own before, or the guy who is a residential electrician.

wish I had as much money as you

Basic electrical stuff is pretty easy. Use your credit card to buy a manual and be $$$$$$$$$$$$$$$$ ahead of things because it will keep being needed to do.

 

[richardshulman]

Hi,
I have spent many hours researching the exact same problem you have. We are not Marina boaters. We are on the anchor or a mooring when cruising. We run two frigs and a chest freezer. We run the generator for a couple of hours before bedding down. Over night we burn 80+ amps. These deep discharges are deadly for our AGM's. My solution is logical pretty simple and very safe. I am using a mixed system. My AGM's and a 200 ah Lithium battery in series with a Battery Bank Manager from Emily and Clarks adventure. This set up protects your alternator and eliminates deep discharge of your AGM'S. The cost is about $500 for the Bank Monitor and $600 for a good Lithium Battery. Installation is quite simple. I have no financial incentive and would be happy to speak with you and point you in the right direction. Dick 1 207 651 0309 at your convenience

 

[mvweebles]

.... There is a lot of garbage out there on the market especially drop-ins and a lot of misinformation as well. Even purpose-built installations go bad witness the EV vehicle fires and the Boeing aircraft fires and the recent car carrier ship fires to name a few. These were all deigned systems, not drop-ins.

Importantly, to emphasize what Tildrider stated, LiFePO4 chemistry is much more stable and than other LFP chemistries; and has lower start and temperature accumulation profile in the event a thermal runaway occurs. Further, BMS's continue to improve to include high-temperature monitoring that will shut-down the battery if thermal runaway does occur.

And garbage batteries are being rapidly displaced by affordable, feature-rich batteries of decent quality that are well documented by folks like Will Prowse and the legions of solar/battery aficianados.

I guess I still scratch my head with a lot of the "Gotta hire an ABYC electrician" guidance. I totally understand that high-amperage DC systems transport and store a lot of potential energy that needs respect. It's not a place for an early DIY'er to try his hand. But that goes for FLA/AGM as well as LFP.

This thread again highlights not the complexity of LFP batteries (they are 12v/24v DC storage vessels), but the vastly broadened potential of a system with LFP batteries. Opens a lot of doors for a cruising boat, though requires more sophisticated monitoring and charging. At least thats how I see it.

Peter

 

[Iggy]

My advice is to always, ALWAYS, hire a qualified marine electrician whenever you make changes to a marine electrical system which involves batteries, chargers, alternators. This excludes the guy on the dock who has done his own before, or the guy who is a residential electrician.

To be very honest about it. If I had to hire a marine electrician every time I would go broke. Or close to it.

Keep in mind that some of use have some sort of back ground in the field. We may not be ABYC certified. But were not dummies in this.

I have completed 2 years now with LifeP04 batteries for my house bank. All good. Did I do research first, yes and a lot of it. But the basics I already knew as most of us here are very knowledgeable.

The problem here is, as in my case. I knew nothing about LifeP04 batteries as most of us did a few years back. But had knowledge of basic wiring and fuse protection. Keep in mind that there is more than one way to do things and this included. But which is the best in every case.

The other side of this. You may be off the docks some where and something happens. Since you set it up the system. Most likely you can fix it. Or at lest know what parts are needed. Maybe come up with a work around.

 

[SteveK]

May be easier to list how not to do an LFP installation. What is different from a FLA bank we (mostly) are familiar with? As the title says swapping a bank of AGM for LifePO4.

 

[Nepidae]

Swapping AGM for LiFePO4 batts

After reading some of the posts on this topic it reminded me of 2 things.

One, was the guy who has never boated and asks what he needs to know to go out on the Loop? He gets responses of; you don't need to get any experience or education, just go do it.

Two, would be, how many of you who suggest that a straight swap out without any changes, would like to share a dock with that boat?

The boat owner obviously doesn't have the knowledge necessary to make proper changes to his boat to support LiFePO4 batts.

When, according to BoatUS, you understand that most boat fires are caused by electrical problems, you might not want to share a dock.

To the boat owner. This project is way above your experience (illustrated by your questions) and the best AND safest way to switch to LiFePO4 batts is to get a qualified (not a home electrician) electrician on your boat to build a system. The system includes all charging points and will involve (probably) changing a lot of your current equipment. Very expensive.

IF you have the space, the better move is L16 AGM batts and 6-8 would be a number that would hold you over night or longer depending on your use.

USE of your power is important. Some manage power so that they can get longer use from their batts. Another thing you might want to consider is solar panels for charging. In FL you would probably find that the solar panels would keep your batts changed as you were using the power.

Call eMarine in FL and discuss with them your wants and needs and they will help you build a system. Much better approach. They may also help you to find a tech to do the installs. Also very important.

Good luck.

 

[tiltrider1]

IF you have the space, the better move is L16 AGM batts and 6-8 would be a number that would hold you over night or longer depending on your use.



Good luck.

I don’t disagree that a little professional help might be a good idea for most.

At the same time most boats that would need 6 to 8 L16 batteries already have programmable inverter chargers. At this point a straight swap and a reprogram of the inverter charger is all that is needed.

I am far more scared of the boater who upgrades from 4 GC batteries to 8 L16 batteries than from some one who upgrades their bank from FLA to LiFePo4.

 

[Don L]

Suggesting L16 instead of LFP batteries on a safety basis, is this some twisted satire thing?

 

[mvweebles]

After reading some of the posts on this topic it reminded me of 2 things.

One, was the guy who has never boated and asks what he needs to know to go out on the Loop? He gets responses of; you don't need to get any experience or education, just go do it.

Two, would be, how many of you who suggest that a straight swap out without any changes, would like to share a dock with that boat?

The boat owner obviously doesn't have the knowledge necessary to make proper changes to his boat to support LiFePO4 batts.

When, according to BoatUS, you understand that most boat fires are caused by electrical problems, you might not want to share a dock.

To the boat owner. This project is way above your experience (illustrated by your questions) and the best AND safest way to switch to LiFePO4 batts is to get a qualified (not a home electrician) electrician on your boat to build a system. The system includes all charging points and will involve (probably) changing a lot of your current equipment. Very expensive.

IF you have the space, the better move is L16 AGM batts and 6-8 would be a number that would hold you over night or longer depending on your use.

USE of your power is important. Some manage power so that they can get longer use from their batts. Another thing you might want to consider is solar panels for charging. In FL you would probably find that the solar panels would keep your batts changed as you were using the power.

Call eMarine in FL and discuss with them your wants and needs and they will help you build a system. Much better approach. They may also help you to find a tech to do the installs. Also very important.

Good luck.

I went back and read the OPs initial post (his only post on this thread). He asked a simple question: is it a simple swap-out? The answer is 'not really.' LiFePO4 batteries have not just a different charge voltage, but a different charge profile. Both of which may vary a bit between manufacturers. Frankly, I didn't get the impression the OP was stepping blindly into a dangerous unknown. He just asked a simple question - a good one at that.

The OP has a LFP-enabled shore charger. What's missing is the underway counterpart - an externally regulated alternator can be programmed to match the battery charge profile. By the time the upgrade is done, around $1500-$2000 in parts plus installation (not including batteries). Good news is that it's a desireable upgrade and on a boat like the Swift Trawler, will likely be done in the next 5-years or so.

Peter

 

[tiltrider1]

Pricing and technology of LiFePo4 has changed so much in the last year that I understand why the majority here are behind the times.

I am not suggesting anyone just buy LiFePo4’s on my word. I am suggesting if your current batteries need replacing you need to review the current LiFePo4 prices and requirements before making a decision.

Prices have come down so much that between September and now that even Server Rack quality LiFePo4’s are cheaper than FLA.

 

[mvweebles]

Pricing and technology of LiFePo4 has changed so much in the last year that I understand why the majority here are behind the times.

I am not suggesting anyone just buy LiFePo4’s on my word. I am suggesting if your current batteries need replacing you need to review the current LiFePo4 prices and requirements before making a decision.

Prices have come down so much that between September and now that even Server Rack quality LiFePo4’s are cheaper than FLA.

I agree. THere is still the barrier of swapping alternator/regulator - as mentioned in my previous post, somewhere in the $1500-$2000 range ($1k for alternator; $500 for regulator; $500 for belt, cabling, etc.). Would be more if custom mounts are needed. But directionally, $2k gets the job done.

Folks can put it off for another battery swap or two. But at some point, it's gonna happen on virtually all boats - think of it as the switch from Incandescent to CFL to LED. Might as well do it sooner rather than later and enjoy the benefits now.

Peter

 

[guy with a boat]

I agree. THere is still the barrier of swapping alternator/regulator - as mentioned in my previous post, somewhere in the $1500-$2000 range ($1k for alternator; $500 for regulator; $500 for belt, cabling, etc.). Would be more if custom mounts are needed. But directionally, $2k gets the job done.

Folks can put it off for another battery swap or two. But at some point, it's gonna happen on virtually all boats - think of it as the switch from Incandescent to CFL to LED. Might as well do it sooner rather than later and enjoy the benefits now.

Peter

Buying L16s is spending a bunch of money for incandescent lighting, and that might be too optimistic. Lead acid (and AGM) batteries are rapidly becoming buggy whips.

 

[tiltrider1]

Buying L16s is spending a bunch of money for incandescent lighting, and that might be too optimistic. Lead acid (and AGM) batteries are rapidly becoming buggy whips.

The rate at which LiFeP04 became affordable and at the rate that the cell's grew in amp hour capacity is staggering. Two years ago I would have gone with FLA on price alone. One year ago I would have been probably too conservative to spend the money on LiFePo4. In September it completely made sense on price alone. Today I would be trying to figure out if I should go with a standard 280ah LiFeP04 or the server rack version at 400ah.

I completely understand the current resistance to LiFePo4. People are just scared of things they don't understand.

 

[SteveK]

For me the decision was easier as my FLA decided it was time to retire them. Of course as soon as they were installed they went on sale.

 

[tiltrider1]

I agree. THere is still the barrier of swapping alternator/regulator - as mentioned in my previous post, somewhere in the $1500-$2000 range ($1k for alternator; $500 for regulator; $500 for belt, cabling, etc.). Would be more if custom mounts are needed. But directionally, $2k gets the job done.

Folks can put it off for another battery swap or two. But at some point, it's gonna happen on virtually all boats - think of it as the switch from Incandescent to CFL to LED. Might as well do it sooner rather than later and enjoy the benefits now.

Peter

Its time to break the alternator discussion into two parts. There are externally regulated alternators, which are common among TF's, not as common with the rest of boaters, capable of high voltage fast charging.

Then there are single wire alternators, which are the most common but not necessarily among TF's, that run at 13.8 volts.

As Peter has mentioned, if you use an externally regulated alternator that was designed to fast charge FLA batteries, you will have to find a way to reprogram it to meet the needs of LiFePo4.

If you have a single wire alternator that puts out only 13.8 volts, all you need to do is find a LiFePo4 battery that is specking 13.8 volts in float mode. There is an additional issue of concern with using a single wire alternator. If the BMS were to shut off the battery the power spike could potentially burn out the diode in the alternator. Now the BMS shutting off is a very unlikely possibility. It is unlikely that with a single wire alternator that the BMS would find the battery over charging. Even if the BMS did shut off the battery, it would need to happen at a time when the boat's consumption of DC was 0. This would never happen on my boat as I have a constantly running A/P pump that I turn on before I start the engines.

It is important that any one thinking of switching to LiFePo4 understand the capabilities of there charger and alternator. Also note that different manufactures spec different bulk and float voltages. Don't assume that all LiFePo4's are the same.

 

[SteveK]

I have two single wire ALT's. My solution was to add 100A of DC2DC chargers from the FLA start batteries. Underway I can charge at 100A into LFP. At anchor the gen feeds a bat charger for the start batteries and the inverter charger another 120A for around 200A into house bank. I am adding another inverter charger to get more short term 120V power for the galley and the by product will increase my charge to around 300A. I have room for another 100A for a 400A total into the 800Ah bank.

 

[Iggy]

This it not that hard. There are many ways to do this. You can change out the Alt and Reg but you don't have to.

Just use a 12v to 12v D.C. charger. Coming off the starting battery to the house bank. You will need to move some wires. And this also protects the Alt.

 

[mvweebles]

This it not that hard. There are many ways to do this. You can change out the Alt and Reg but you don't have to.

Just use a 12v to 12v D.C. charger. Coming off the starting battery to the house bank. You will need to move some wires. And this also protects the Alt.

Post before yours from Steve K did this. Note use of plural chargers. Expense adds up, plus space, plus cabling, etc. Sure it's an alternative to multi-stage externally regulated alternator, but the benefits seem elusive to me. Why not just setup the correct system in the first place rather than a workaround?

have two single wire ALT's. My solution was to add 100A of DC2DC chargers from the FLA start batteries

Few TF folks make prolonged runs so having a constant alternator output wouldn't be a problem I suppose. According to the OEM, my Lion Energy LFPs are perfectly happy at 13.9v constant (I must add that their support has been vague and elusive when it comes to anything remotely technical, a stark contrast to other battery builders such as Battle Born who have very specific recommendations).

This thread is far from the first LFP discussion on TF, but has been helpful for me. As Guy With a Boat observed, the future is LFP. An owner can put it off for until the next upgrade cycle, but at some point, not upgrading and adapting the alternator is wasting time and money. Not saying that day is today. But it's damn close. At least that's my observation of typical adoption of new technology as it will apply to house battery banks in cruise-capable boats.

Peter

 

[Don L]

I believe the problem is that till recent all the LFP boat systems you read on forums were expensive boat science projects. The DIY boaters were looking to do the "best" installation to protect their expensive batteries.

I also believe that there is a lot of confusion that falls into the "everyone knows that" which just doesn't matter even if it is correct.

I will repeat my story; a year ago when I left to go cruising for 6 months I found out I needed batteries and needed them fast. I ended up with 4 x 100ah Power Queen LFPs and those weren't even the brand I met to get as I got so confused and met to get ones I had convinced myself were "better". I cruised 6 months off grid and they were fine and this included some long motor legs of 12+ hours. I have NO lithium battery charger settings on any charge source on my boat. I reprogramed the solar setting for the batteries. I also adjusted the settings in my Balmar ARS-5 regulator to only get to 14.1V for 12 minutes and then go to float of 13.4v. I reduced output of my regulator to about 80% via the regulator (I already had it at 85%). When I have to use the generator and the battery charger I have it set to an AGM setting that only does 14.1V and then 13.5v float (I charge up and just turn it off anyway and don't normally even get the batteries fully charged because it doesn't matter).

So I got $300/100ah drop-ins, dropped them in, spend 15 minutes adjusting setpoints and then took off for the Bahamas for 6 months of anchoring out. It was simple and I spend more time in reading the over complex details than doing it. I don't even have any of the battery to battery chargers everyone seems to get.

I feel talk about about needing to change boat stuff is over posted. If you have a boat with internal regulators etc. you were already past due to change those. Most semi modern battery chargers are going to have a AGM or Gel battery setting that is going to be fine. If your boat doesn't have you probably don't even have a need for LFPs.

 

[Iggy]

Post before yours from Steve K did this. Note use of plural chargers. Expense adds up, plus space, plus cabling, etc. Sure it's an alternative to multi-stage externally regulated alternator, but the benefits seem elusive to me. Why not just setup the correct system in the first place rather than a workaround?



Few TF folks make prolonged runs so having a constant alternator output wouldn't be a problem I suppose. According to the OEM, my Lion Energy LFPs are perfectly happy at 13.9v constant (I must add that their support has been vague and elusive when it comes to anything remotely technical, a stark contrast to other battery builders such as Battle Born who have very specific recommendations).

This thread is far from the first LFP discussion on TF, but has been helpful for me. As Guy With a Boat observed, the future is LFP. An owner can put it off for until the next upgrade cycle, but at some point, not upgrading and adapting the alternator is wasting time and money. Not saying that day is today. But it's damn close. At least that's my observation of typical adoption of new technology as it will apply to house battery banks in cruise-capable boats.

Peter

I don't think it is really a work around. I am not saying its the only way, but one way.

Can you use a LFP as a starting battery? Only if the LFP bank is big enough. So AGM or flooded battery is still needed and needs to be re-charged. Or at lest, for the moment until one is developed. What happens and it not likely but it could, the BMS shuts down with the ALT connected to the house bank. Can the starting bank now be use with the LFP Atl and Reg? If yes, for how long?

Some will say, yes a LFP can be used for cranking. The answer to this question largely depends on the application. But this is a whole other topic!

This way it also protects that Alt since the starting battery is connected to it. Two switches can be installed if the BMS did shut down. One disconnecting the house bank and the other connecting the starting battery to the house loads. In theory, you could run for days until the problem is fixed.

Two years ago when I looked at ABYC rules on this. They wanted a 2nd source, if the BMS did shuts down. But these rules could have changed over time. In other words, running the whole boat off the stating bank to get you home. So the BMS is a factor when buying expansive or inexpensive batteries as Will P. has mentioned.

Oh well, to each his own. And good luck to all on how you setup your system.

Just as a FYI. On BMS, you may want to look at? Can the firmware be upgraded? Can you remote into the battery? Some have a display? Some battery's have a port to communicate with each other which is another topic. As in the Kilolvault battery, there is a port for that but they have not written the firmware to support that yet.

 

[mvweebles]

re: LFP start battery. They exist. They're expensive, and mostly built for racing applications where weight counts. I installed an Anti-Gravity start battery for my 20hp Tohatsu with electric start and tilt. Fits in a small weatherproof box I mounted to the transom of my AB 310 AL dink. Works like a charm. Weights under 2-lbs.

Here's the automotive version of the same battery. 1500 cranking amps with a 're-start' reserve feature that acts as a jump-start if needed. Note, these only state they are "Lithium Ion" and not the specific chemistry.

https://antigravitybatteries.com/products/starter-batteries/automotive/ag-t6-rs/

Peter

 

[Helmsman]

It looks like there will be a revision to the ABYC E-11 electrical wiring guideline. This will probably be around July. From what I have read on MTOA, there will be significant changes to the portion of E-11 that discusses lithium batteries. That can and probably will lead to issues with current installs. It might be prudent to wait on the update if you can.

 

[Iggy]

Too late! Now going on year 3.

 

[SteveK]

It looks like there will be a revision to the ABYC E-11 electrical wiring guideline. This will probably be around July. From what I have read on MTOA, there will be significant changes to the portion of E-11 that discusses lithium batteries. That can and probably will lead to issues with current installs. It might be prudent to wait on the update if you can.

July 2024? I thought that was done in 2023. A member of ABYC needs to confirm.